Steel alloy

ABSTRACT

A low alloy steel having titanium as an essential alloying ingredient. The titanium addition provides the means for controlling and manipulating the fragment mass distribution characteristics emanating from the detonation of an explosive warhead fabricated from the titanium containing steel alloy.

United States Patent [191 Watmough et a].

I STEEL ALLOY P. OShea, Lombard, both of 111.

Assignee: The United States of America as represented by the Secretary of the Air Force, Washington, DC.

Filed:

App]. No.:

US. Cl. 75/126 D, 75/126 E, 102/67 Int. Cl. C22c 39/26, F42b 13/48 Field of Search 75/126 R, 126 D,

75/126 E, 123 N, 123 L; 102/67 References Cited UNITED STATES PATENTS Inventors: Thomas Watmough, Dolton; Robert Jan. 15, 1974 ,2,737,455 3/1956 Kirkby ct al. 75/126 D 2,683,086 7/1954 Clark 75/126 D 1 2,040,189 5/1936 Strauss 75/126 D 3,547,032 12/1970 Horvath 102/67 7 FOREIGN PATENTS OR APPLICATIONS 1,200,423 7/1970 Great Britain 75/126 D OTHER PUBLICATIONS Roberts et a1., Tool Steels, 3rd Ed. American Society for Metals, Metals Park, Ohio, 1962, pp. 227, 718.

Primary Examiner-Carl D. Quarforth Assistant ExaminerR. E. Schafer Attorney--I-larry A. Herbert, Jr. et a1.

[5 7 ABSTRACT A low alloy steel having titanium as an essential alloying ingredient. The titanium addition provides the means for controlling and manipulating the fragment mass distribution characteristics emanating from the detonation of an explosive warhead fabricated from the titanium containing steel alloy.

4 Claims, 2 Drawing F ig iires STEEL ALLOY Still another another object of this invention is to provide a structural material that possesses the type of fragment mass distribution characteristics that make it BACKGROUND OF THE NVENTION useful in the manufacture of explosive warheads for use This invention relates to a low alloy steel having tita- 5 against both light and heavy military targets.

nium as an alloying ingredient. in a more particular The above and still further objects and advantages of manner, this invention is concerned with the use of titathe. present invention will become readily apparent nium as a means for controlling the fragmentation upon consideration of the following detailed descripcharacteristics of low alloy tempered martensitic steels tion thereof when taken in conjunction with the followused in warheads. ing drawings.

The distribution patterns and fragmentation characteristics of steel fragments produced by a detonating DESCRIPTION OF THE DRAWINGS warhead is a problem of great concern to those respon- In the drawings; sible for the fabrication and design of antipersonnel FIG 1 and 2 are graphical representations showing and antivehiele p The effectiveness of E the effects of titanium content on the fragment mass flades, artillery and monol' Shells, aerial bombs and distribution characteristics of the alloys of this invenother explosive warheads depends to a great extent tion, 1 upon the fragmentation characteristics of the materials used to fabricate such weapons. In an attempt to im- DESCRIPTION OF THE PREFERRED prove their fragmentation effects, it has been found EMBODIMENTS that the incorporation of titanium as an essential alloy- Th fragmentation ll of hi invention are low ing ingredient in low alloy tempered martensitic steels ll steels f di carbon content h possess 3 provides a component that is extremely useful as a tempered martensitic structure. The addition of titastructural material for warheads. it provides a means nium, as an essential alloying ingredient, provides the for controlling the fragment mass distribution effect in me ns f prod i an embrittl d ferrit tructure such a manner that the weapons can be employed that controls the fragmentation characteristics of the against both light and heavy targets. martensitic steel alloys of this invention.

The titaniu'm is incorporated in the alloy in specified SUMMARY 0F THE INVENTION amounts in accordance with conventional alloying In accordance with the broad concept of this inventechniques. The titanium is a ferrite strengthener and tion, it has been found that the inclusion of titanium in carbide stabilizer and produces the embrittled struclow alloy steels having a tempered martensitic structure ture which controls the fragmentation characteristics provides a means for controlling the fragment mass disof the alloy. A medium carbon low alloy steel of varytribution characteristics of those alloys when they are 3 5 ing composition, with three levels of titanium, was seemployed in the manufacture of explosive warheads. lected to verify if titanium additions could control the The titanium is a ferrite strengthener and a carbide stafragmentation effects in both forged and cast steels. bilizer and as such can provide an embrittled structure The compositions of the steel alloys of this invention that controls fragmentation. are given in Table I.

TABLE I COMPOSITION OF 'l'll'ANIUM-BRARING Steels Final Analysis, weight percent Example Structure C Mn Si Cr V 'lii Fe 1 Forged 0.51 1.30 0.50 1.16 0.21 0.28 hill 2 Forged 0.51 1.36 0.42 1.23 0.22 0.16 3 Forged 0.53 1.30 0.36 1.19 0.31 0.03 4 Cast 0.56 1.38 0.32 1.24 0.25 0.02 5 Cast 0.50 1.32 0.35 1.19 0.24 0.21 6 Cast 0.51 1.35 0.45 1.24 0.22 0.40

The alloys find utility as a structural material in the Heat treatment of the alloys in Table I were confabrication of explosive warheads for use against both ducted in accordance with known hardening techlight and heavy military targets. For example, antiperniques so that large grained martensitic metallurgical sonnel grenades, artillary and mortar shells, i l structures with a titanium rich grain boundary network bombs as well as other explosive devices which utilize were producedfragment pieces as a weapon can make use of the alloys Test results indicated that the higher the titanium of hi invention content, the finer the fragmentation. These results are graphically shown in FIG. 1 and 2 of the drawings. From these results it can be seen that the addition of titanium to steels, which have been properly heat treated, produces a titaniumrich network that can be v H I utilized to control fragmentation. Utilization of the Another object of this invention is to provide a low techniques of this invention allows for the simple proalloy steel whose fragmentation characteristics are conduction of naturally fragmenting warheads. By selectrolled by the inclusion of titanium as an alloying ingretion of titanium content, warheads for use against both dienl. light and heavy targets can be obtained.

Accordingly, the primary object of this invention is to provide an alloy steel that possesses desirable fragmentation characteristics when used in fabricating explosive warheads.

From an examination of the foregoing, it can be seen that the present invention provides a means for controlling the fragmentation characteristics of steel alloys in a simple and efficient manner. The invention provides steel alloys that are especially useful as structural materials in the fabrication of explosive warheads for use against military targets.

While the principle of this ivention has been pointed out with particularity, it should be understood that various modifications and alterations can be made without departing from the spirit thereof, the scope of which is defined by the appended claims.

What is claimed is:

about 0.40 percent titanium. 

2. An alLoy in accordance with claim 1 containing about 0.02 percent titanium.
 3. An alloy in accordance with claim 1 containing about 0.21 percent titanium.
 4. An alloy in accordance with claim 1 containing about 0.40 percent titanium. 